man/systemd.service.xml

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   7   This file is part of systemd.
   8
   9   Copyright 2010 Lennart Poettering
  10
  11   systemd is free software; you can redistribute it and/or modify it
  12   under the terms of the GNU Lesser General Public License as published by
  13   the Free Software Foundation; either version 2.1 of the License, or
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  19   Lesser General Public License for more details.
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  24
  25 <refentry id="systemd.service">
  26         <refentryinfo>
  27                 <title>systemd.service</title>
  28                 <productname>systemd</productname>
  29
  30                 <authorgroup>
  31                         <author>
  32                                 <contrib>Developer</contrib>
  33                                 <firstname>Lennart</firstname>
  34                                 <surname>Poettering</surname>
  35                                 <email>lennart@poettering.net</email>
  36                         </author>
  37                 </authorgroup>
  38         </refentryinfo>
  39
  40         <refmeta>
  41                 <refentrytitle>systemd.service</refentrytitle>
  42                 <manvolnum>5</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>systemd.service</refname>
  47                 <refpurpose>Service unit configuration</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <para><filename>systemd.service</filename></para>
  52         </refsynopsisdiv>
  53
  54         <refsect1>
  55                 <title>Description</title>
  56
  57                 <para>A unit configuration file whose name ends in
  58                 <filename>.service</filename> encodes information
  59                 about a process controlled and supervised by
  60                 systemd.</para>
  61
  62                 <para>This man page lists the configuration options
  63                 specific to this unit type. See
  64                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  65                 for the common options of all unit configuration
  66                 files. The common configuration items are configured
  67                 in the generic <literal>[Unit]</literal> and
  68                 <literal>[Install]</literal> sections. The service
  69                 specific configuration options are configured in the
  70                 <literal>[Service]</literal> section.</para>
  71
  72                 <para>Additional options are listed in
  73                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
  74                 which define the execution environment the commands
  75                 are executed in, and in
  76                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
  77                 which define the way the processes of the service are
  78                 terminated.</para>
  79
  80                 <para>Unless <varname>DefaultDependencies=</varname>
  81                 is set to <option>false</option>, service units will
  82                 implicitly have dependencies of type
  83                 <varname>Requires=</varname> and
  84                 <varname>After=</varname> on
  85                 <filename>basic.target</filename> as well as
  86                 dependencies of type <varname>Conflicts=</varname> and
  87                 <varname>Before=</varname> on
  88                 <filename>shutdown.target</filename>. These ensure
  89                 that normal service units pull in basic system
  90                 initialization, and are terminated cleanly prior to
  91                 system shutdown. Only services involved with early
  92                 boot or late system shutdown should disable this
  93                 option.</para>
  94
  95                 <para>If a service is requested under a certain name
  96                 but no unit configuration file is found, systemd looks
  97                 for a SysV init script by the same name (with the
  98                 <filename>.service</filename> suffix removed) and
  99                 dynamically creates a service unit from that
 100                 script. This is useful for compatibility with
 101                 SysV. Note that this compatibility is quite
 102                 comprehensive but not 100%. For details about the
 103                 incomptibilities see the <ulink
 104                 url="http://www.freedesktop.org/wiki/Software/systemd/Incompatibilities">Incompatibilities
 105                 with SysV</ulink> document.
 106                 </para>
 107         </refsect1>
 108
 109         <refsect1>
 110                 <title>Options</title>
 111
 112                 <para>Service files must include a
 113                 <literal>[Service]</literal> section, which carries
 114                 information about the service and the process it
 115                 supervises. A number of options that may be used in
 116                 this section are shared with other unit types. These
 117                 options are documented in
 118                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 119                 and
 120                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
 121                 options specific to the <literal>[Service]</literal>
 122                 section of service units are the following:</para>
 123
 124                 <variablelist>
 125                         <varlistentry>
 126                                 <term><varname>Type=</varname></term>
 127
 128                                 <listitem><para>Configures the process
 129                                 start-up type for this service
 130                                 unit. One of <option>simple</option>,
 131                                 <option>forking</option>,
 132                                 <option>oneshot</option>,
 133                                 <option>dbus</option>,
 134                                 <option>notify</option> or
 135                                 <option>idle</option>.</para>
 136
 137                                 <para>If set to
 138                                 <option>simple</option> (the default
 139                                 value if <varname>BusName=</varname>
 140                                 is not specified) it is expected that
 141                                 the process configured with
 142                                 <varname>ExecStart=</varname> is the
 143                                 main process of the service. In this
 144                                 mode, if the process offers
 145                                 functionality to other processes on
 146                                 the system its communication channels
 147                                 should be installed before the daemon
 148                                 is started up (e.g. sockets set up by
 149                                 systemd, via socket activation), as
 150                                 systemd will immediately proceed
 151                                 starting follow-up units.</para>
 152
 153                                 <para>If set to
 154                                 <option>forking</option> it is
 155                                 expected that the process configured
 156                                 with <varname>ExecStart=</varname>
 157                                 will call <function>fork()</function>
 158                                 as part of its start-up. The parent process is
 159                                 expected to exit when start-up is
 160                                 complete and all communication
 161                                 channels set up. The child continues
 162                                 to run as the main daemon
 163                                 process. This is the behaviour of
 164                                 traditional UNIX daemons. If this
 165                                 setting is used, it is recommended to
 166                                 also use the
 167                                 <varname>PIDFile=</varname> option, so
 168                                 that systemd can identify the main
 169                                 process of the daemon. systemd will
 170                                 proceed starting follow-up units as
 171                                 soon as the parent process
 172                                 exits.</para>
 173
 174                                 <para>Behaviour of
 175                                 <option>oneshot</option> is similar
 176                                 to <option>simple</option>, however
 177                                 it is expected that the process has to
 178                                 exit before systemd starts follow-up
 179                                 units. <varname>RemainAfterExit=</varname>
 180                                 is particularly useful for this type
 181                                 of service.</para>
 182
 183                                 <para>Behaviour of
 184                                 <option>dbus</option> is similar to
 185                                 <option>simple</option>, however it is
 186                                 expected that the daemon acquires a
 187                                 name on the D-Bus bus, as configured
 188                                 by
 189                                 <varname>BusName=</varname>. systemd
 190                                 will proceed starting follow-up units
 191                                 after the D-Bus bus name has been
 192                                 acquired. Service units with this
 193                                 option configured implicitly gain
 194                                 dependencies on the
 195                                 <filename>dbus.socket</filename>
 196                                 unit. This type is the default if
 197                                 <varname>BusName=</varname> is
 198                                 specified.</para>
 199
 200                                 <para>Behaviour of
 201                                 <option>notify</option> is similar to
 202                                 <option>simple</option>, however it is
 203                                 expected that the daemon sends a
 204                                 notification message via
 205                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 206                                 or an equivalent call when it finished
 207                                 starting up. systemd will proceed
 208                                 starting follow-up units after this
 209                                 notification message has been sent. If
 210                                 this option is used
 211                                 <varname>NotifyAccess=</varname> (see
 212                                 below) should be set to open access to
 213                                 the notification socket provided by
 214                                 systemd. If
 215                                 <varname>NotifyAccess=</varname> is
 216                                 not set, it will be implicitly set to
 217                                 <option>main</option>.</para>
 218
 219                                 <para>Behaviour of
 220                                 <option>idle</option> is very similar
 221                                 to <option>simple</option>, however
 222                                 actual execution of a the service
 223                                 binary is delayed until all jobs are
 224                                 dispatched. This may be used to avoid
 225                                 interleaving of output of shell
 226                                 services with the status output on the
 227                                 console.</para>
 228                                 </listitem>
 229                         </varlistentry>
 230
 231                         <varlistentry>
 232                                 <term><varname>RemainAfterExit=</varname></term>
 233
 234                                 <listitem><para>Takes a boolean value
 235                                 that specifies whether the service
 236                                 shall be considered active even when
 237                                 all its processes exited. Defaults to
 238                                 <option>no</option>.</para>
 239                                 </listitem>
 240                         </varlistentry>
 241
 242                         <varlistentry>
 243                                 <term><varname>GuessMainPID=</varname></term>
 244
 245                                 <listitem><para>Takes a boolean value
 246                                 that specifies whether systemd should
 247                                 try to guess the main PID of a service
 248                                 should if it cannot be determined
 249                                 reliably. This option is ignored
 250                                 unless <option>Type=forking</option>
 251                                 is set and <option>PIDFile=</option>
 252                                 is unset because for the other types
 253                                 or with an explicitly configured PID
 254                                 file the main PID is always known. The
 255                                 guessing algorithm might come to
 256                                 incorrect conclusions if a daemon
 257                                 consists of more than one process. If
 258                                 the main PID cannot be determined
 259                                 failure detection and automatic
 260                                 restarting of a service will not work
 261                                 reliably. Defaults to
 262                                 <option>yes</option>.</para>
 263                                 </listitem>
 264                         </varlistentry>
 265
 266                         <varlistentry>
 267                                 <term><varname>PIDFile=</varname></term>
 268
 269                                 <listitem><para>Takes an absolute file
 270                                 name pointing to the PID file of this
 271                                 daemon. Use of this option is
 272                                 recommended for services where
 273                                 <varname>Type=</varname> is set to
 274                                 <option>forking</option>. systemd will
 275                                 read the PID of the main process of
 276                                 the daemon after start-up of the
 277                                 service. systemd will not write to the
 278                                 file configured here.</para>
 279                                 </listitem>
 280                         </varlistentry>
 281
 282                         <varlistentry>
 283                                 <term><varname>BusName=</varname></term>
 284
 285                                 <listitem><para>Takes a D-Bus bus
 286                                 name, where this service is reachable
 287                                 as. This option is mandatory for
 288                                 services where
 289                                 <varname>Type=</varname> is set to
 290                                 <option>dbus</option>, but its use
 291                                 is otherwise recommended as well if
 292                                 the process takes a name on the D-Bus
 293                                 bus.</para>
 294                                 </listitem>
 295                         </varlistentry>
 296
 297                         <varlistentry>
 298                                 <term><varname>ExecStart=</varname></term>
 299                                 <listitem><para>Takes a command line
 300                                 that is executed when this service
 301                                 shall be started up. The first token
 302                                 of the command line must be an
 303                                 absolute file name, then followed by
 304                                 arguments for the process. It is
 305                                 mandatory to set this option for all
 306                                 services. This option may not be
 307                                 specified more than once, except when
 308                                 <varname>Type=oneshot</varname> is
 309                                 used in which case more than one
 310                                 <varname>ExecStart=</varname> line is
 311                                 accepted which are then invoked one by
 312                                 one, sequentially in the order they
 313                                 appear in the unit file.</para>
 314
 315                                 <para>Optionally, if the absolute file
 316                                 name is prefixed with
 317                                 <literal>@</literal>, the second token
 318                                 will be passed as
 319                                 <literal>argv[0]</literal> to the
 320                                 executed process, followed by the
 321                                 further arguments specified. If the
 322                                 first token is prefixed with
 323                                 <literal>-</literal> an exit code of
 324                                 the command normally considered a
 325                                 failure (i.e. non-zero exit status or
 326                                 abnormal exit due to signal) is ignored
 327                                 and considered success. If both
 328                                 <literal>-</literal> and
 329                                 <literal>@</literal> are used for the
 330                                 same command the former must precede
 331                                 the latter. Unless
 332                                 <varname>Type=forking</varname> is
 333                                 set, the process started via this
 334                                 command line will be considered the
 335                                 main process of the daemon. The
 336                                 command line accepts % specifiers as
 337                                 described in
 338                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
 339
 340                                 <para>On top of that basic environment
 341                                 variable substitution is
 342                                 supported. Use
 343                                 <literal>${FOO}</literal> as part of a
 344                                 word, or as word of its own on the
 345                                 command line, in which case it will be
 346                                 replaced by the value of the
 347                                 environment variable including all
 348                                 whitespace it contains, resulting in a
 349                                 single argument.  Use
 350                                 <literal>$FOO</literal> as a separate
 351                                 word on the command line, in which
 352                                 case it will be replaced by the value
 353                                 of the environment variable split up
 354                                 at whitespace, resulting in no or more
 355                                 arguments. Note that the first
 356                                 argument (i.e. the program to execute)
 357                                 may not be a variable, and must be a
 358                                 literal and absolute path
 359                                 name.</para></listitem>
 360                         </varlistentry>
 361
 362                         <varlistentry>
 363                                 <term><varname>ExecStartPre=</varname></term>
 364                                 <term><varname>ExecStartPost=</varname></term>
 365                                 <listitem><para>Additional commands
 366                                 that are executed before (resp. after)
 367                                 the command in
 368                                 <varname>ExecStart=</varname>. Multiple
 369                                 command lines may be concatenated in a
 370                                 single directive, by separating them
 371                                 by semicolons (these semicolons must
 372                                 be passed as separate words). In that
 373                                 case, the commands are executed one
 374                                 after the other,
 375                                 serially. Alternatively, these
 376                                 directives may be specified more than
 377                                 once with the same effect. However,
 378                                 the latter syntax is not recommended
 379                                 for compatibility with parsers
 380                                 suitable for XDG
 381                                 <filename>.desktop</filename> files.
 382                                 Use of these settings is
 383                                 optional. Specifier and environment
 384                                 variable substitution is
 385                                 supported.</para></listitem>
 386                         </varlistentry>
 387
 388                         <varlistentry>
 389                                 <term><varname>ExecReload=</varname></term>
 390                                 <listitem><para>Commands to execute to
 391                                 trigger a configuration reload in the
 392                                 service. This argument takes multiple
 393                                 command lines, following the same
 394                                 scheme as pointed out for
 395                                 <varname>ExecStartPre=</varname>
 396                                 above. Use of this setting is
 397                                 optional. Specifier and environment
 398                                 variable substitution is supported
 399                                 here following the same scheme as for
 400                                 <varname>ExecStart=</varname>. One
 401                                 special environment variable is set:
 402                                 if known <literal>$MAINPID</literal> is
 403                                 set to the main process of the
 404                                 daemon, and may be used for command
 405                                 lines like the following:
 406                                 <command>/bin/kill -HUP
 407                                 $MAINPID</command>.</para></listitem>
 408                         </varlistentry>
 409
 410                         <varlistentry>
 411                                 <term><varname>ExecStop=</varname></term>
 412                                 <listitem><para>Commands to execute to
 413                                 stop the service started via
 414                                 <varname>ExecStart=</varname>. This
 415                                 argument takes multiple command lines,
 416                                 following the same scheme as pointed
 417                                 out for
 418                                 <varname>ExecStartPre=</varname>
 419                                 above. Use of this setting is
 420                                 optional. All processes remaining for
 421                                 a service after the commands
 422                                 configured in this option are run are
 423                                 terminated according to the
 424                                 <varname>KillMode=</varname> setting
 425                                 (see
 426                                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>). If
 427                                 this option is not specified the
 428                                 process is terminated right-away when
 429                                 service stop is requested. Specifier
 430                                 and environment variable substitution
 431                                 is supported (including
 432                                 <literal>$MAINPID</literal>, see
 433                                 above).</para></listitem>
 434                         </varlistentry>
 435
 436                         <varlistentry>
 437                                 <term><varname>ExecStopPost=</varname></term>
 438                                 <listitem><para>Additional commands
 439                                 that are executed after the service
 440                                 was stopped using the commands
 441                                 configured in
 442                                 <varname>ExecStop=</varname>. This
 443                                 argument takes multiple command lines,
 444                                 following the same scheme as pointed
 445                                 out for
 446                                 <varname>ExecStartPre</varname>. Use
 447                                 of these settings is
 448                                 optional. Specifier and environment
 449                                 variable substitution is
 450                                 supported.</para></listitem>
 451                         </varlistentry>
 452
 453                         <varlistentry>
 454                                 <term><varname>RestartSec=</varname></term>
 455                                 <listitem><para>Configures the time to
 456                                 sleep before restarting a service (as
 457                                 configured with
 458                                 <varname>Restart=</varname>). Takes a
 459                                 unit-less value in seconds, or a time
 460                                 span value such as "5min
 461                                 20s". Defaults to
 462                                 100ms.</para></listitem>
 463                         </varlistentry>
 464
 465                         <varlistentry>
 466                                 <term><varname>TimeoutStartSec=</varname></term>
 467                                 <listitem><para>Configures the time to
 468                                 wait for start-up. If a
 469                                 daemon service does not signal
 470                                 start-up completion within the
 471                                 configured time, the service will be
 472                                 considered failed and be shut down
 473                                 again.
 474                                 Takes a unit-less value in seconds, or a
 475                                 time span value such as "5min
 476                                 20s". Pass 0 to disable the timeout
 477                                 logic. Defaults to 90s, except when
 478                                 <varname>Type=oneshot</varname> is
 479                                 used in which case the timeout
 480                                 is disabled by default.
 481                                 </para></listitem>
 482                         </varlistentry>
 483
 484                         <varlistentry>
 485                                 <term><varname>TimeoutStopSec=</varname></term>
 486                                 <listitem><para>Configures the time to
 487                                 wait for stop. If a service is asked
 488                                 to stop but does not terminate in the
 489                                 specified time, it will be terminated
 490                                 forcibly via SIGTERM, and after
 491                                 another delay of this time with
 492                                 SIGKILL (See
 493                                 <varname>KillMode=</varname>
 494                                 in <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
 495                                 Takes a unit-less value in seconds, or a
 496                                 time span value such as "5min
 497                                 20s". Pass 0 to disable the timeout
 498                                 logic. Defaults to 90s.
 499                                 </para></listitem>
 500                         </varlistentry>
 501
 502                         <varlistentry>
 503                                 <term><varname>TimeoutSec=</varname></term>
 504                                 <listitem><para>A shorthand for configuring
 505                                 both <varname>TimeoutStartSec=</varname>
 506                                 and <varname>TimeoutStopSec=</varname>
 507                                 to the specified value.
 508                                 </para></listitem>
 509                         </varlistentry>
 510
 511                         <varlistentry>
 512                                 <term><varname>WatchdogSec=</varname></term>
 513                                 <listitem><para>Configures the
 514                                 watchdog timeout for a service. This
 515                                 is activated when the start-up is
 516                                 completed. The service must call
 517                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 518                                 regularly with "WATCHDOG=1" (i.e. the
 519                                 "keep-alive ping"). If the time
 520                                 between two such calls is larger than
 521                                 the configured time then the service
 522                                 is placed in a failure state. By
 523                                 setting <varname>Restart=</varname> to
 524                                 <option>on-failure</option> or
 525                                 <option>always</option> the service
 526                                 will be automatically restarted. The
 527                                 time configured here will be passed to
 528                                 the executed service process in the
 529                                 <varname>WATCHDOG_USEC=</varname>
 530                                 environment variable. This allows
 531                                 daemons to automatically enable the
 532                                 keep-alive pinging logic if watchdog
 533                                 support is enabled for the service. If
 534                                 this option is used
 535                                 <varname>NotifyAccess=</varname> (see
 536                                 below) should be set to open access to
 537                                 the notification socket provided by
 538                                 systemd. If
 539                                 <varname>NotifyAccess=</varname> is
 540                                 not set, it will be implicitly set to
 541                                 <option>main</option>. Defaults to 0,
 542                                 which disables this
 543                                 feature.</para></listitem>
 544                         </varlistentry>
 545
 546                         <varlistentry>
 547                                 <term><varname>Restart=</varname></term>
 548                                 <listitem><para>Configures whether the
 549                                 main service process shall be
 550                                 restarted when it exits. Takes one of
 551                                 <option>no</option>,
 552                                 <option>on-success</option>,
 553                                 <option>on-failure</option>,
 554                                 <option>on-abort</option> or
 555                                 <option>always</option>. If set to
 556                                 <option>no</option> (the default) the
 557                                 service will not be restarted when it
 558                                 exits. If set to
 559                                 <option>on-success</option> it will be
 560                                 restarted only when it exited cleanly,
 561                                 i.e. terminated with an exit code of
 562                                 0. If set to
 563                                 <option>on-failure</option> it will be
 564                                 restarted only when it exited with an
 565                                 exit code not equalling 0, when
 566                                 terminated by a signal (including on
 567                                 core dump), when an operation (such as
 568                                 service reload) times out or when the
 569                                 configured watchdog timeout is
 570                                 triggered. If set to
 571                                 <option>on-abort</option> it will be
 572                                 restarted only if it exits due to
 573                                 reception of an uncaught signal
 574                                 (including on core dump). If set to
 575                                 <option>always</option> the service
 576                                 will be restarted regardless whether
 577                                 it exited cleanly or not, got
 578                                 terminated abnormally by a signal or
 579                                 hit a timeout.</para></listitem>
 580                         </varlistentry>
 581
 582                         <varlistentry>
 583                                 <term><varname>PermissionsStartOnly=</varname></term>
 584                                 <listitem><para>Takes a boolean
 585                                 argument. If true, the permission
 586                                 related execution options as
 587                                 configured with
 588                                 <varname>User=</varname> and similar
 589                                 options (see
 590                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 591                                 for more information) are only applied
 592                                 to the process started with
 593                                 <varname>ExecStart=</varname>, and not
 594                                 to the various other
 595                                 <varname>ExecStartPre=</varname>,
 596                                 <varname>ExecStartPost=</varname>,
 597                                 <varname>ExecReload=</varname>,
 598                                 <varname>ExecStop=</varname>,
 599                                 <varname>ExecStopPost=</varname>
 600                                 commands. If false, the setting is
 601                                 applied to all configured commands the
 602                                 same way. Defaults to
 603                                 false.</para></listitem>
 604                         </varlistentry>
 605
 606                         <varlistentry>
 607                                 <term><varname>RootDirectoryStartOnly=</varname></term>
 608                                 <listitem><para>Takes a boolean
 609                                 argument. If true, the root directory
 610                                 as configured with the
 611                                 <varname>RootDirectory=</varname>
 612                                 option (see
 613                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 614                                 for more information) is only applied
 615                                 to the process started with
 616                                 <varname>ExecStart=</varname>, and not
 617                                 to the various other
 618                                 <varname>ExecStartPre=</varname>,
 619                                 <varname>ExecStartPost=</varname>,
 620                                 <varname>ExecReload=</varname>,
 621                                 <varname>ExecStop=</varname>,
 622                                 <varname>ExecStopPost=</varname>
 623                                 commands. If false, the setting is
 624                                 applied to all configured commands the
 625                                 same way. Defaults to
 626                                 false.</para></listitem>
 627                         </varlistentry>
 628
 629                         <varlistentry>
 630                                 <term><varname>NonBlocking=</varname></term>
 631                                 <listitem><para>Set O_NONBLOCK flag
 632                                 for all file descriptors passed via
 633                                 socket-based activation. If true, all
 634                                 file descriptors >= 3 (i.e. all except
 635                                 STDIN/STDOUT/STDERR) will have
 636                                 the O_NONBLOCK flag set and hence are in
 637                                 non-blocking mode. This option is only
 638                                 useful in conjunction with a socket
 639                                 unit, as described in
 640                                 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Defaults
 641                                 to false.</para></listitem>
 642                         </varlistentry>
 643
 644                         <varlistentry>
 645                                 <term><varname>NotifyAccess=</varname></term>
 646                                 <listitem><para>Controls access to the
 647                                 service status notification socket, as
 648                                 accessible via the
 649                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 650                                 call. Takes one of
 651                                 <option>none</option> (the default),
 652                                 <option>main</option> or
 653                                 <option>all</option>. If
 654                                 <option>none</option> no daemon status
 655                                 updates are accepted from the service
 656                                 processes, all status update messages
 657                                 are ignored. If <option>main</option>
 658                                 only service updates sent from the
 659                                 main process of the service are
 660                                 accepted. If <option>all</option> all
 661                                 services updates from all members of
 662                                 the service's control group are
 663                                 accepted. This option should be set to
 664                                 open access to the notification socket
 665                                 when using
 666                                 <varname>Type=notify</varname> or
 667                                 <varname>WatchdogUsec=</varname> (see
 668                                 above). If those options are used but
 669                                 <varname>NotifyAccess=</varname> not
 670                                 configured it will be implicitly set
 671                                 to
 672                                 <option>main</option>.</para></listitem>
 673                         </varlistentry>
 674
 675                         <varlistentry>
 676                                 <term><varname>Sockets=</varname></term>
 677                                 <listitem><para>Specifies the name of
 678                                 the socket units this service shall
 679                                 inherit the sockets from when the
 680                                 service is started. Normally it
 681                                 should not be necessary to use this
 682                                 setting as all sockets whose unit
 683                                 shares the same name as the service
 684                                 (ignoring the different suffix of course)
 685                                 are passed to the spawned
 686                                 process.</para>
 687
 688                                 <para>Note that the same socket may be
 689                                 passed to multiple processes at the
 690                                 same time. Also note that a different
 691                                 service may be activated on incoming
 692                                 traffic than inherits the sockets. Or
 693                                 in other words: The
 694                                 <varname>Service=</varname> setting of
 695                                 <filename>.socket</filename> units
 696                                 doesn't have to match the inverse of the
 697                                 <varname>Sockets=</varname> setting of
 698                                 the <filename>.service</filename> it
 699                                 refers to.</para></listitem>
 700                         </varlistentry>
 701
 702                         <varlistentry>
 703                                 <term><varname>StartLimitInterval=</varname></term>
 704                                 <term><varname>StartLimitBurst=</varname></term>
 705
 706                                 <listitem><para>Configure service
 707                                 start rate limiting. By default
 708                                 services which are started more often
 709                                 than 5 times within 10s are not
 710                                 permitted to start any more times
 711                                 until the 10s interval ends. With
 712                                 these two options this rate limiting
 713                                 may be modified. Use
 714                                 <varname>StartLimitInterval=</varname>
 715                                 to configure the checking interval
 716                                 (defaults to 10s, set to 0 to disable
 717                                 any kind of rate limiting). Use
 718                                 <varname>StartLimitBurst=</varname> to
 719                                 configure how many starts per interval
 720                                 are allowed (defaults to 5). These
 721                                 configuration options are particularly
 722                                 useful in conjunction with
 723                                 <varname>Restart=</varname>, however
 724                                 apply to all kinds of starts
 725                                 (including manual), not just those
 726                                 triggered by the
 727                                 <varname>Restart=</varname> logic.
 728                                 Note that units which are configured
 729                                 for <varname>Restart=</varname> and
 730                                 which reach the start limit are not
 731                                 attempted to be restarted anymore,
 732                                 however they may still be restarted
 733                                 manually at a later point from which
 734                                 point on the restart logic is again
 735                                 activated. Note that
 736                                 <command>systemctl
 737                                 reset-failed</command> will cause the
 738                                 restart rate counter for a service to
 739                                 be flushed, which is useful if the
 740                                 administrator wants to manually start
 741                                 a service and the start limit
 742                                 interferes with
 743                                 that.</para></listitem>
 744                         </varlistentry>
 745
 746                         <varlistentry>
 747                                 <term><varname>StartLimitAction=</varname></term>
 748
 749                                 <listitem><para>Configure the action
 750                                 to take if the rate limit configured
 751                                 with
 752                                 <varname>StartLimitInterval=</varname>
 753                                 and
 754                                 <varname>StartLimitBurst=</varname> is
 755                                 hit. Takes one of
 756                                 <option>none</option>,
 757                                 <option>reboot</option>,
 758                                 <option>reboot-force</option> or
 759                                 <option>reboot-immediate</option>. If
 760                                 <option>none</option> is set,
 761                                 hitting the rate limit will trigger no
 762                                 action besides that the start will not
 763                                 be
 764                                 permitted. <option>reboot</option>
 765                                 causes a reboot following the normal
 766                                 shutdown procedure (i.e. equivalent to
 767                                 <command>systemctl reboot</command>),
 768                                 <option>reboot-force</option> causes
 769                                 an forced reboot which will terminate
 770                                 all processes forcibly but should
 771                                 cause no dirty file systems on reboot
 772                                 (i.e. equivalent to <command>systemctl
 773                                 reboot -f</command>) and
 774                                 <option>reboot-immediate</option>
 775                                 causes immediate execution of the
 776                                 <citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 777                                 system call, which might result in
 778                                 data loss.  Defaults to
 779                                 <option>none</option>.</para></listitem>
 780                         </varlistentry>
 781
 782                 </variablelist>
 783
 784                 <para>Check
 785                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 786                 and
 787                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 788                 for more settings.</para>
 789
 790         </refsect1>
 791
 792         <refsect1>
 793                 <title>Compatibility Options</title>
 794
 795                 <para>The following options are also available in the
 796                 <literal>[Service]</literal> section, but exist purely
 797                 for compatibility reasons and should not be used in
 798                 newly written service files.</para>
 799
 800                 <variablelist>
 801                         <varlistentry>
 802                                 <term><varname>SysVStartPriority=</varname></term>
 803                                 <listitem><para>Set the SysV start
 804                                 priority to use to order this service
 805                                 in relation to SysV services lacking
 806                                 LSB headers. This option is only
 807                                 necessary to fix ordering in relation
 808                                 to legacy SysV services, that have no
 809                                 ordering information encoded in the
 810                                 script headers. As such it should only
 811                                 be used as temporary compatibility
 812                                 option, and not be used in new unit
 813                                 files. Almost always it is a better
 814                                 choice to add explicit ordering
 815                                 directives via
 816                                 <varname>After=</varname> or
 817                                 <varname>Before=</varname>,
 818                                 instead. For more details see
 819                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
 820                                 used, pass an integer value in the
 821                                 range 0-99.</para></listitem>
 822                         </varlistentry>
 823
 824                         <varlistentry>
 825                                 <term><varname>FsckPassNo=</varname></term>
 826                                 <listitem><para>Set the fsck passno
 827                                 priority to use to order this service
 828                                 in relation to other file system
 829                                 checking services. This option is only
 830                                 necessary to fix ordering in relation
 831                                 to fsck jobs automatically created for
 832                                 all <filename>/etc/fstab</filename>
 833                                 entries with a value in the fs_passno
 834                                 column > 0. As such it should only be
 835                                 used as option for fsck
 836                                 services. Almost always it is a better
 837                                 choice to add explicit ordering
 838                                 directives via
 839                                 <varname>After=</varname> or
 840                                 <varname>Before=</varname>,
 841                                 instead. For more details see
 842                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
 843                                 used, pass an integer value in the
 844                                 same range as
 845                                 <filename>/etc/fstab</filename>'s
 846                                 fs_passno column. See
 847                                 <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 848                                 for details.</para></listitem>
 849                         </varlistentry>
 850
 851                 </variablelist>
 852         </refsect1>
 853
 854         <refsect1>
 855                   <title>See Also</title>
 856                   <para>
 857                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 858                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 859                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 860                           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 861                           <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 862                   </para>
 863         </refsect1>
 864
 865 </refentry>